Sep 24, 2021 · Instead of onion gravy, make the steak and gravy with a packet of mushroom gravy or plain brown gravy. Sauté about 6 to 8 ounces of mushrooms in a small amount of butter or oil until softened. Add them to the sauce mixture. Add about 1 cup of sliced onions to the slow cooker before adding the steak. I ended up with a WONDERFUL meal. I took the following suggestions: I added chopped onion and garlic to meat mixture before browning. I added a can of cream of mushroom soup to French onion soup, and mixed in a small amount of brown gravy mix to give it some color and thickened it up a bit.